<?php

/**
 * @author blog.anchen8.net
 * @copyright 2015
 */
 error_reporting(E_ALL^E_NOTICE);
 $i=0;
 $arr=array();
while($i<20000){
    $key = floor($i/10000);
   $randStr = str_shuffle('ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890');
            
			$rand = substr($randStr,0,6);
            $isRepeat=false;
            
            for($q=0;$q<$key;$q++){
                if(in_array($rand, $arr[$q])){
                    $isRepeat=true;
                    $i++;
                }
            }
            
            if($isRepeat === false){
                $arr[$key][]=$rand;
                $i++;
            }
            
}



echo count($arr[0])."-";
echo count($arr[1])."-";
echo count($arr[2])."-";
echo count($arr[3])."-";
echo count($arr[4])."-";
?>